Chemical oxygen generators include a cartridge containing a chemical charge and have a starting device at one end of the cartridge. The starting device is in the form of an ignition device and an oxygen outlet is provided in the end of the cartridge lying opposite the ignition device. After activating the ignition device, the chemical charge releases oxygen in an exothermal reaction with the oxygen leaving the cartridge through the oxygen outlet. The chemical charge can, for example, be sodium chlorate with additives. The reaction front runs from the ignition device to the oxygen outlet. The oxygen quantity (the oxygen flow) supplied per unit of time and the time duration of this supply are dependent upon the geometry of the chemical charge and the formulation of this charge. Furthermore, flow and supply duration can be influenced by the reaction-control members.
Swiss Patent 139,956 discloses an oxygen generator wherein the chemical charge is provided with a slit starting at the ignition end and running parallelly to the reaction front and into the region of the opposite-lying end. An insulating plate is inserted into the slit as a partition element which prevents the reaction from jumping over to the other side. The chemical charge reacts first only on one side of the insulating plate when the chemical charge is ignited. The reaction front runs to the opposite lying end and here jumps over to the other side of the insulating plate and, on this side, runs back to the ignition end. In this way, approximately twice the running time with half the flow of the generator is obtained compared with an embodiment without the partition element.
It is a disadvantage in this generator that the flow and supply duration cannot be influenced beyond the strictly geometric doubling of the reaction path.
Swiss Patent 183,336 discloses a chemical oxygen generator which is partitioned into segments by partition walls extending in the longitudinal direction. However, no information is provided as to the material of the partition walls and the function thereof. The description however permits the assumption to be made that the partition walls are made of paraffinated asbestos board.
Swiss Patent 180,448 discloses a generator having component partition walls made of asbestos or metal coated with paraffin. These walls are arranged transversely to the direction of movement of the reaction front. The walls uniformly distribute the gas flowing through the generator. The paraffin coating apparently is provided only as a protection against corrosion.
The two last-mentioned patents provide no suggestion as to how the flow and running time of a generator can be influenced with built-in walls.